As people are utilizing computing devices for an increasing variety of tasks, there is a corresponding need to improve the security available for these tasks. While many conventional approaches rely on password entry for user authentication, these passwords can be stolen or discovered by other persons who can impersonate the user for any of a variety of tasks. Further, the entry of these passwords on portable devices is not user friendly in many cases, as the small touchscreen or keyboard elements can be difficult to accurately select using a relatively large human finger, and can require the user to turn away from friends or co-workers when entering a password, which can be awkward or embarrassing in many situations. In order to avoid typing in long passwords in such situations, users often have their passwords stored on their devices or enable information to be stored elsewhere such that an activity can be performed without manually re-entering the password. When using such an approach, however, another person having access to that device can impersonate the user for any task associated with the store password. As a compromise some users utilize short and simple passwords, but these passwords can be easily hacked by an unscrupulous user or application. Certain approaches attempt to improve security by adding biometric identification. For example, a computing device might capture an image of a user and analyze that image to attempt to recognize the user using facial recognition software. Such a process provides only a certain level of additional protection, however, as the facial recognition process can often be spoofed by holding a picture of the user in front of the camera, as the resulting two-dimensional image can look substantially the same whether taken of the user or a picture of the user.